Photoelectric control for game devices



Aug; 5,1947. J. A. MacLAGAN, ETAL PHOTOELECTRIC common FOR GAME DEVICES Filed Aug. 25, 1945 mmvron. time: 4. Nada ya BY 7770402 Patented Aug. 5, 1947 rno'roanac'rarc CONTROL FOR GAME navrces James A. MacLagan, Forest Park, and Thaddeus A. Walsh, Chicago, Ill., asslgnors to Pioneer Trust & Savings Bank of Chicago, astrustee Original application June 25, 1942, Serial No.

Divided and this application August as, 1945, Serial No. 612,612

4 Claims.

The present invention relates generally to signaling devices and more particularly to foul deiecting means for games and recreational contests such as bowling.

The present invention is an improvement in certain respects upon our automatic foul line keeper for which application for Letters Patent, Serial No. 389,976, filed April 23, 1941, has been made, reference to same being made herein to 'the extent subject matter in common may be haze might exist and operate a lire alarm before heat developed is enough to set off other well known detectors, or, as where the sole of the shoe on the foot of a player committing a foul interrupts only a portion of the beam.

Another object of the invention is to provide an improved photo-electric circuit which will energize a coil or the like by means of a change in capacity in the photo-electric cell as distinguished for instance from changes in inductance or conductivity of the cathode.

A further object of the invention is to provide an improved detector of fouls at the foul line where the passage or'presence of a bowling ball upon the foul line or a sudden fall in the voltage powering the circuit will not register a false foul.

Another object of the invention is to, provide a set of interlocked circuits immediately responsive to interruptance, one of which prevents operation of the signal as long as it is interrupted and another of which prevents the operation of the signal before it is interrupted.

Another object of the invention is to provide a compact and simple unit of equipment which is inexpensive and can be readily installed upon -a bowling alley and serviced easily from time to time; as required.

Another object of the invention is to provide a foul detector for bowling alleys characterized by a streamlined arrangement of parts with those subject to damage located below the alley bed.

These being among the objects of the present invention, other and further objects will become apparent from the drawings, the description relating thereto and the appended claims.

Fig. 1 is a vertical section taken longitudinally through a bowling alley indicating the arrange- 2 ment and preferred construction of the interlocked devices that detect infractions of the rules of play;

Fig. 2 is a fragmentary view, a part of'which is enlarged, taken from above the alley shown in Fig. 1;

Fig. 3 is a photo-electrical controls and their interlock employed to detect infractions of rules of play at the foul line.

Referring now to the drawings more specifically, the bowling alley indicated at l0 comprises a bed ll divided by a foul line l2 into a runway it upon one side and a varnished portion l4 upon the other side over which theball l5 travels to reach and strike the bowling pins l6 that are set up on the far end of the alley. Along both sides of the varnished portion, the alley i0 is bounded by gutters l1 and the gutters by rails i8, each rail separating adjacent alleys one from another where more than one alley is installed.

At the ends of the rails l8 that are adjacent the foul line l2, the rails are cut away as at 20 to receive a box 2| in which are mounted in shielded relationship the light sources for the photo-electric beams and the two photo-electric cells and also, preferably, the circuits which are employed to detect infractions of rules of play at the foul line.

More particularly, in each box is provided a light source 22 for one of the alleys and the photo-electric receiver for the beam of light projected over an adjacent alley, each box 2| being identical between alleys to serve as a source of light to project the beams to the adjacent photoelectric receiver over one alley on one side and to act as a receiver for the beams of light projected from another box over another alley on the other side.

Because of this arrangement, the two sources of light for the beams occupy a very small space in each box and in the rest of the box there is room enough for all of the simplified photo-electric equipment provided by the present invention. Although it is possible to place the photo-electric control circuits elsewhere, if upon occasion such is deemed to be desirable, it is preferred that the photo-electric circuits be mounted in the box so that from a service and stray capacity viewpoint one box or unit can be removed in event of failure, repair or insertion of new tubes, and replaced by another unit ready to operate that need only be adjusted to its nvironment, which adjustment can be done with little trouble.

In such an installation, live rubber grommets diagrammatical showing of the are employed to secure the box in place at widely spaced points to eliminate vibration and Provide stability. In fact, where the units are original equipment for the alley, a yoke separate from and disposed under the alley boards may be employed to link all the boxes together as an independent floating unit supported upon the under supports of the alley with extensive rubber cushions provided to absorb shock.

Moreparticularly, for each alley two beams of light are arranged one above the other, the top one 23 being located where it is interrupted by a ball approaching the foul line before the lower beam 23 is interrupted, and is the last of the two beamsto be re-established as the ballrolls beyond the foul line, it being impossible thereby to interrupt the lower beam 24 with a bowling ball without interrupting the top beam 21 first.

The lower beam 2| is a wide beam with its greatest width disposed in a vertical plane as more particularly described in our application Serial No. 389,976, reference to which is hereby made.

Furthermore, if desired, a trip beam 25 may be employed down the alley a short way to control a normally open switch 26 that prevents registering an infraction as a foul unless the ball is released to pass down th alley. Interruptance of the beam 28 operates to close the switch It by means of a circuit similar to that controlled by beam 23.

Furthermore, another circuit similar to that controlled by the beam 23, which will be described later, may be controlled by a beam 21 located just in front of the pine is to open a normally closed switch 28 when a ball passes that point to prevent a player committing an intentional foul when he sees that the ball has struck the pins and left them in such a way as to providethe player with a difllcult second try. The photoelectric controls 25 and 21 and the operation of the switches 28 and 28 will be described further in their relation to the photo-electric controls 23 and 24, it being understood that the photoelectric controls 25 and 21 can be dispensed with in any installation if the results provided y them are not desired by the alley owner.

From light sources 22 the beams run substantially longitudinally of the alley to fall upon mirrors 30 that direct the rays across the alley at the foul line l2 and against mirrors II on the other side of the alley which in turn direct the beams against other mirrors 32 and 33, respectively, and by the last mirrors the beams are directed downwardl against photo-electric cells, a photo-electric cell 34 being disposed in the path of one beam beneath an aperture 35 and a photo electric cell 35 being disposed in the path of another beam beneath an aperture 31. The apertures are cut in the intermediate framework or shield 39 of the box 2i.

Condensing lenses 38 disposed in the path of the beams provide parallel rays of light in the beams where they cross the alley, and provide focal points for the beams at the photo-electric cells. Asidefrom the relative location of the photo-electric cells in the box along with their circuits, the construction is similar in many respects to that disclosed in our application Serial No. 389,976, reference to which is hereby made for further details to the extent that they might be of interest.

Referring now to Fig. 3, a gong l and a foul signal lamp 4| are powered independently from an A. C. house line 49 through a step (lQ ll trans- 4 former n, if desired, which provides a voltage of from 8 to 32 volts as controlled by a switch (not shown) in the referee's booth, depending upon manufacturing expedients and the desires of alley owners. The lamp and gong, preferably a single stroke gong or chime, are connected in parallel with each other and with the switch ll of a normally open relay ll for automatic operation. The relay has a self-energizing circuit it connected to one of the contacts of the switch to energize the relay and the switch it controls and hold the switch closed once it is enerlllled. until such time as a normally closed bi-metal timing switch 41 breaks after application of heat by a heater unit ll.

The relay ll is powered from the current source 42, through the conductor I00, the normally closed relay switch It, conductor ill, the normally opened switch It, conductor Ill, the coil of the relay 4', conductor IIII, the normally opened switch I2, conductors I and Ill, normally closed switch 41, and conductor I. As an alternative, the relay ll, once actuated, closes the switches ll, after which the energization of the relay ll is self supported through conductors I00 and till, the lower of the switches 04, conductor I03, switches 52 and 41 and conductors I05 and I00.

In addition to the energization of the relay is being self supporting, current is passed through the heater coil 48 from the lower of the switches 44 through conductors Ill and I". The upper of the switches 44 actuates the bell and alarm through conductors I00, III, III, switch ll, and conductors I05 and I as controlled by the timer switch 41.

The normally closed relay switch ll is held open by the coil Ila as described in connection with the trip beam 25 located where it will detect the release of the ball. The switch It is disposed preferably in the foul signal circuit 48 so that it does not interfere with the action of the relay 45, but rather cooperates with its action,being in series with the switch 44 thereof.

The relays 53a and 53b difler from relay "I in that they act quickly but have a delayed recovery from their resting position once the resting position is attained.

For a" better understanding of the general organization of the photo-electric circuits as they control the relays, it is the intention to use the beam 23 and relay device 52, 53 to lock out the system instantly whenever the ball goes-through and to return the system to operation instantly when the ball clears the beam ll. The lower or wide beam relay device 50, BI is instantly responsive to slight or partial interruptance of the beam 24. Until the beam 21 has been interrupted the relay device 44, It may be closed by the interruptance of the beam it alone and held closed by the timer 41, 48. Then, when the ball trips the beam 26, signifying that it has been released and put into play, the switch It closes and operates the signals 40 and to indicate that the infraction interrupting the beam 24 was .a foul; On the other hand, i! a foul has not been committed until after the ball interrupts the trip beam 25, closure of the switch it merely sets up the circuit controlled by the relay and the lower beam registers a foul if committed before the ball interrupts the beam 21.

Referring further to Fig. 3, and the details of the circuit controlling the relay device M, ii including the lower or wide beam 24, this circuit or,a light interruptance of less than 10% of the beam will set off the system even though the system is adjusted on the safe side of a resting time when the cell is illuminatedby'the full beam.

condition, thus providing a detector which can.

be used in fire alarm systems and other connections as well as the one shown herein for foul detection.

In the particular system illustrated, although a vacuum envelope can be used, an electron emission device, preferably a gas-filled envelope of the hot cathode, tetrode type such as an R; C. A. Thyratron #2050 or #2051 tube is employed wherein the usual anode (3) 6|, cathode(8) 52 I heated by the filament (2) (1) as and control grid 85 are provided along with a grid (6) 54 which will be referred to hereafter as the screened grid. y

The system is powered preferably by a .120 watt auto transformer 65 having a low voltage secondary 81 connected in circuitwith the filament I3, with or without a filament control (not shown), which control is preferably dispensed with for the sakeof simplicity and economy, as being not indispensable.

The cathode i2 is connected in circuit with one end I0 of the auto transformer 55 through the relayjl as bridged by a'condenser ll toprevent chattering in the coil. This end 10 of the auto "transformer 63 may be referred to as-the positive end since the tube 80 is inherently a half wave rectifier in that the current in the anode circuit II has a direct current component flowing half the time, so to speak, from the anode to the cathode, the electron fiow being in the opposite direction. I

By way of augmenting the flow of electrons through the tube from the cathode 32 to the anode 8|, the screen grid 04 and cathode are connected .to the positive side of the filament ('7) 63 to provide greater cathode area and reduce capacities between the filament and anode, thereby providing a-large potential or path for electron emission to keep the coil of the relay 5] energized. Although 120 volt A.'C. current is employed, the positive end may be the positive pole of a 120 D. C. pulsating current substituted to provide the essential characteristics herein discussed.

turn is negatively biased through a -15 megohm resistor 15 in circuit with the center or movable tap of a 400 ohm potentiometer 10, one end 11 of which is connected to the negative" pole of the auto transformer 35. The other end 80 of the potentiometer I6 is connected to the positive side of the filament 53 along with the screened grid and cathode, and this connection BI .is bridged to the anode ll of the cell 31 by a 500 ohm resistor 32.

The characteristics of the mined by the type of cell 31 employed, having preferably substantially the same current characterlstic as the cell when the cell is fully illuminated. Then the potentiometer I5 is adjusted to accommodate the cell characteristics and to a Thus the loss of control of the tube which permits electron emission and current fiow to energize the relay 5| is due to the setting of the potentiometer in relation to the value of the light falling upon the cell 31. Electron flow through the cell isat the highest, and since the current through the cell is operating in relation to the center, tap which is less negative than that derived through the resistor 15, the control grid 65 of the tube 60 is less negative than it should be to control the tube.

When the cell 31 is shadowed the current flow through the cell lowers, and the negative pole 18 of the transformer, through the resistor 15, swings the bias on the control grid 65 to increase the negative characteristic thereof with respect to the cathode 62 and the control grid takes control of the tube during the negative or off-cycle of thecurrent when current is not flowing through the tube, the anode of the tube having current only during one-half'of the A, C. cycle.

The photo-electric circuit controlling the relay 4 53 as regards the interruptance of the beam 23 is a peak-interruptance circuit employing an "R. C. A. tube #41, 83, in which the photo-electric 84 with the cathode 14a biased negatively by the.

negative pole 18a through a 15 megohm resistor 15a to take control of the tube 83 through the control grid 85 connected thereto when the light beam 23 is interrupted and the cell 32 darkened. The relay 53 is de-energized when the cell 32 is darkened;

Circuits like the one just described for cell 32 can be used to control the operation of relays 53a and 53b with regard to interruptance of beams 25 and 21 respectively.

A further point of interest regarding the operating characteristics of the present invention is the one relating to sudden drops in the line voltage in the supply current. Both the lower beam resistor" are deter- 24 circuit and the upper 'beam 23 circuit are affected by a voltage drop. However, the lower beam circuit as described is less sensitive to voltage drops than the peak interruptance circuit employed with the upper 'beam and therefore the switch 52 is opened by de-energization of the relay 53 before the switch 50 is dropped by the relay 5|. Thereby the effect is substantially thesame as though a ball interrupted the top beam 23 before interrupting the lower beam '24. No false fouls are called, which might otherwise occur with voltage drops.

Manyof the steps of operation have already been described, but, in review, when a player advances to the foul line l2 to place the ball in play by delivering it down the alley in the direction of the pins l6, any infractions of the rules of play at the foul line will be detected by the beam 24 and registered by the relay 45 closing the switch 44 and sustaining the closure as timed by the timer 41'. Whetherthe ball has been released before or after the infraction, the registry will be established since, if the ball interrupts the beam, 23, the relay 45 is released or locked out only to let the ball go through and, if the infraction takes place or continues to exist after the ball has been released, the moment the upper beamsized 23 is reestablished the relay 45 will be ener- Energization of the relay 45, however, does not point where. the control grid loses control of the 15 sound the signal and register the foul imme- 7 diately unless the beam 25 is dispensed with, in which case the foul will be immediately recorded. If the beam 25 is employed in any particular installation, the recording of the foul will not be made until the beam is interrupted and the switch 26 permitted to close.

The beam 25, when employed, is installed far enough down the alley that it is unlikely that a ball will be thrown over it, and low enough upon the alley to catch the ball rolling past it. Although it is desirable to have the beam as close to the foul line as possible to apprise the player of his Poul as soon as possible for psychological reasons, the distance the beam 25 is beyondthe' foul line is not critical so long as a slow-moving ball will interrupt it within the timing period of the timer 41. Thus a foul is registered and then recorded if the ball has been put into play.

In order to prevent a player committing an intentional foul to better his chances on a second try or to prevent facetious fouling merely to work the apparatus after the play or the ball has been completed, it is preferred that a beam 21 be located just in front of the pins to remove the foul detector from operation at or shortly after the ball has struck the pins It. This particular arrangement is described and claimed in our above mentioned copending application.

In some respects we are not able to account fully for the improved results which are obtained by the apparatus and arrangement of elements and circuits of this invention, and it should be understood that any attempt to analyze the theory or theories believed to be responsible for these results is to be construed not as defining a mode of operation but merely as a possible explanation of certain physical, electrical or capacity phenomena which have been observed.

Although certain embodiments and preferred arrangements of the elements of the present invention have been shown and described herein, it will be apparent to those skilled in the art that various uses, modifications and changes may be made without departing from the spirit and substance of the invention, the scope of which is commensurate with the appended claims.

What is claimed is:

1. In a photo-electric system, two vertically spaced beams of undulating energy. circuit means including a signal and a plurality of relays connected in series, one normally open and another normally closed, a photo-electric cell energized by the lower oi the two beams, an electron emission device having an anode connected in circuit with the normally closed relay, a control grid connected to the cathode of the cell and biased by said upper beam and controlling said normally open s- 2. In a photo-electric system, the combination 7 of a hot cathode tetrode electron emission tube, a Photo-electric cell having the cathode thereof connected to the control grid of the tube, an auto transformer having an intermediate tap connected to the anode of the cell, resistance means bridging the tap and one pole of the transformer, high resistance means biasing said control grid to th bridge at a tap intermediate the ends of said resistance means, a connection between the tube cathode and a second tap on the resistance means intermediate the first and the anode connection.

3. In a photo-electric control the combination of a source of pulsating current, a photo-electric cell having an anode and cathode, an electron emission gas-filled tube having a cathode, anode, control grid, and screening grid, the tube control grid being connected to the cell cathode and biased negatively through a high resistor to the negative pole of the pulsating current, and the cell anode being connected to the source of current at a point having a bias intermediate thel negative and positive poles.

4. In a photo-electric system, a tetrod valve, a source of pulsating current including an auto transformer having an intermediate tap, a photoelectric cell. said valve having the anode thereof connected to ,one pole of the auto transformer through a control device, the anode of the cell being connected to the intermediate tap, and bridged to the other pole of the auto transformer through resistance, said valve having its control rid connected directly to the cell cathode and biased to the bridge at a point intermediate the ends of the resistance through a resistor having substantially the same current flow capacity as the photo-electric cell when the cell is subjected to a source of undulating energy.

JAMES A. MAOLAGAN. THADDEUS A. WALSH.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,140,350 Dawson Dec. 13, 1938 2,170,157 Pray Aug. 22, 1939 2,231,621 Goodridge Feb. 11. 1941 

